1. Field of the Invention
This invention relates to an excavating or earthmoving apparatus and, more particularly, is directed to an improved tillage point which is attached to the shank of excavating or earthmoving apparatuses, such as backhoes, dozers, and rippers.
The invention further relates to an improved construction of a tillage point which provides better wear and heat resistance and easier penetration into the ground or soil, thereby reducing the amount of drag and friction exerted against the excavating or earthmoving apparatus.
The invention can be used on a variety of excavating and earthmoving apparatuses and is very cost effective due to its ease of operation and increased life. Both of these apparatuses are described more fully herein, along with the method of construction.
2. DESCRIPTION OF THE PRIOR ART
Various prior art tillage points used in earthmoving devices, as well as the apparatuses and methods of their construction in general, are known and are found to be exemplary of the U.S. prior art. They are:
______________________________________ U.S. Pat. No. Inventor ______________________________________ 1,488,398 W. H. Kline 1,927,818 M. M. Brodersen 2,738,602 C. R. Meeks 2,932,100 G. L. Goethe 3,063,176 D. S. Larson 3,305,029 D. L. Shelton 3,326,302 H. H. Washband et al 3,708,895 N. N. Griffith et al 3,729,845 J. S. Flippin 3,774,324 G. Y. Lafand 3,959,901 G. R. Klett 3,970,445 P. Gale et al 4,028,823 G. Edwards et al 4,037,337 C. W. Hemphill 4,103,442 H. R. Zepf 4,136,469 H. R. Zepf 4,182,058 A. Poncin 4,446,927 F. E. Robertson ______________________________________
U.S. Pat. No. 1,488,398, issued to Kline, discloses a plow point which is attached and detached to a plow share. Although it is used in an earthmoving apparatus, it has a very limited application.
U.S. Pat. No. 1,927,818, issued to Brodersen, discloses a ripper tooth for use in earth, rock, and especially road working tools and comprises a penetrating edge constructed of a material having a greater resistance to wear than the material of the body of the ripper tooth. Thus the body would wear out faster and the invention is more costly.
U.S. Pat. No. 2,738,602, issued to Meeks, discloses a replacement point for the teeth of buckets used in earthmoving equipment and comprises a pyramidical body which is welded to the bucket teeth.
U.S. Pat. No. 2,932,100, issued to Goethe, discloses a land clearing and brush raking attachment for tractor type vehicles.
U.S. Pat. No. 3,063,176, issued to Larson, discloses a hard, replaceable-ripper tip used on the teeth of earthmoving apparatuses. It comprises a blade that is secured to the blade housing by a weld and a retaining pin that secures the blade housing to the shank of the earthmoving vehicle. This device differs from the present invention in that the Larson patent uses a blade that has a very blunt edge and uses a weld that secures it to the blade housing, as opposed to having a solid cast as the present invention does.
U.S. Pat. No. 3,774,324, issued to Lafand, discloses a replaceable two-part digger tooth for earth moving shovels, diggers, and the like. The point of the tooth is held onto the shank by two pins. However, as in the Larson patent, the Lafand patent uses a very blunt edge.
U.S. Pat. No. 3,970,445, issued to Gale et al, discloses a wear resistant alloy comprising boron, chromium, and iron having maximum hardness for a given composition and produced by rapidly cooling and solidifying spheroidal particles of a molten alloy mixture. This material is used in a highly abrasive environment or ground engaging tool, such as ripper tips, bucket teeth, and cutting edges of various types of earthworking machines. Although the Gale patent does disclose usage of a chromium alloy, it does not disclose the unique shape of the present invention.
These patents or known prior uses all teach and disclose various types of teeth used on earthmoving apparatuses of sorts and of various manufacturers, and the like, as well as methods of their construction. However, none of them, whether taken singly or in combination, discloses the specific details of the combination of the invention in such a way as to bear upon the claims of the present invention.